1. Field
Example embodiments relate to display devices, and more particularly, to electrowetting display devices.
2. Description of the Related Art
Most display devices, including current mobile display devices or large display devices, may be transmission-type display devices, e.g., transparent liquid crystal displays (LCDs) that use a backlight unit as a light source. However, when transmission-type display devices are used outdoors, the brightness and contrast thereof may be degraded due to external light, leading to a reduction in visibility. In particular, transmission-type LCDs consume a relatively large amount of power because liquid crystals of the transmission-type LCDs have lower light transmissivity and a voltage needs to be continuously applied to form an image. For this reason, application of reflection-type display devices to mobile products has been attempted. The reflection-type display devices use external light, and thus consume less power and have improved visibility in outdoor settings compared with the transmission-type display devices in outdoor settings. Reflection-type display devices are being researched to provide higher reflectivity, higher contrast, and a higher gray scale representation capability in order to secure image quality at the same level as printed images.
Display devices using electrowetting form images by controlling the intensity and wavelength band of light that passes through each pixel using a principle in which the wetting characteristics of a surface may be changed according to voltage. Such display devices using electrowetting do not use a polarization plate, and thus, may improve reflectivity or transmissivity at least twice as much when compared with LCDs. In addition, such display devices using electrowetting have a response speed of about 10 ms or less, which may be relatively fast.